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1.
In rats fed with high-cholesterol (HC) chow, the renal specimens were investigated by microscopy and enzymehistochemistry. The levels of serum lipids, 24 h urinary protein excretion ( UPE ), N-acetyl-β-D-glucosaminidase (NAG) and Nitric Oxide (NO) were evaluated. Histological examination showed cell swelling, break-down and massive lipid deposition in renal tubules; perivascular and interstitial cell infiltration and mesangial cell proliferation. Enzymehistochemistry demonstrated that lactate dehydrogenase (LDH) activity in proximal tubular epithelial cells increased but succino dehydrogenase (SDH) activity decreased. The NO level in serum, urine and renal cortex were all decreased (p〈0.01). Urinary NO, was negatively correlated with urinary NAG and UPE (r is -0. 525, 0. 529 respectively, p〈0.01). This study shows that a HC diet can induce the early morphological changes in the whole kidney, particularly in the renal tubules. The decrease of NO is associated with the pathogenesis of hypercholesterolemia-induced renal injury.  相似文献   

2.
The influence of two main characteristics of steel fiber, the aspect ratio (Df) and volume fraction (ρf), on the bending strength of Layered Steel Fiber Reinforced Concrete (LSFRC) is investigated by using orthogonal test. Via the variance analysis on the experimental results and trend analysis on the two characteristics, Df is found significantly related to the bending strength of LSFRC. The influence ratio is 63.3%. The bending strength of LSFRC increases if Df increases, makes better when Df reaches 100. ρf has ordinary influence on the bending strength of LSFRC. The influence ratio is 29.2%. Other characteristics, such as the shape of steel fiber and the mix proportion, have less influence. The best ρf contributing to the bending strength of LSFRC is 1.5 %. If ρf is greater than 1.5%, it has negative influence on the bending strength of LSFRC. So, ρf makes a limited contribution to the bending strength of LSFRC.  相似文献   

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4.
A novel method to synthesize 2,6-bis(p-aminophenyl)benzo[1,2-d;5,4-d′]bisoxazole using 1,2,3-trichlorobenzene as the starting material through nitration, substitution, hydrogenation, and condensation was reported. During the condensation, the influence of the amount of SnCl2 on the yield of the product was studied. The electron spectra of the compound were discussed, the results showed that it is a fluorescence material with large Stokes shift. Foundation item: Supported by the High Technology Research and Development Program of China (2002AA305109) Biography: Chen Xiang qun (1969), female, Ph. D candidate, research direction: organic and polymer materials.  相似文献   

5.
目的 :探讨中药复方“更可宁”对去卵巢大鼠血脂谱的影响。方法 :以苯甲酸雌二醇注射剂为对照 ,观察“更可宁”对去卵巢大鼠血清HDLc、LDLc、CH、TG及HDLc/CH等值的影响。结果 :与去卵巢空白对照组比较 ,“更可宁”、雌二醇均能降低去卵巢大鼠TG值并升高其HDLc、HDLc/CH值 ,差异均有统计学意义(P <0 .0 5 ) ;二者同时还能降低去卵巢大鼠CH、LDLc值 ,但差异均无统计学意义 (P >0 .0 5 )。结论 :中药复方“更可宁”能有效调节去卵巢大鼠血脂 ,提示其具有防治动脉粥样硬化或冠心病的作用  相似文献   

6.
To investigate the combined effects of Cd^2+ ( 0,10,100,500 μmol/L) , acetochlor (AC) (0,1.6,4.0,8.0μmol/L), and bensulfuronmethyl (BSM) ( 0,0.16,0.40,0.80 μmol/L) on the biomass,leaf soluble sugar, total chlorophyll (chl) content, chl a/b ratio, and Cd content in roots and shoots in the rice seedlings, pot culture experiments were conducted with rice (Oryza sativa L. ) cultivar Jinyou 402. The results showed that the Cd and AC combined treatment (Cd+ AC treatment) significantly inhibited the growth of the roots and shoots. The root dry weight/shoot dry weight (RDW/SDW) ratio, total chlorophyll content and chl a/b ratio decreased by 41%, 50%, 56% , respectively, in comparison with the control, as well as the leaf soluble sugar content, plant dry weight /plant fresh weight (PDW/PFW) ratio increased by 284% and 44% , respectively. Cd content in the roots and shoots had a decreasing tendency with the increasing concentration of AC under the Cd+AC treatment. The Cd and BSM combined treatment (Cd+BSM treatment) had a similar result to the Cd+AC treatment. The results suggest that the toxicity of Cd to rice seedlings has been enhanced due to its combination with herbicides.  相似文献   

7.
Isoetes sinensis Palmer (Isoetaceae) is an aquatic or amphibious plant that is critically endangered in China. Previous studies have revealed the crassulacean acid metabolism (CAM)-like photosynthetic pathway occurs commonly in submerged leaves in genusIsoetes. Water chemistry parameters and the titratable acidity content of the plant extract were measured from samples obtained in the early morning (7∶00) and late afternoon (15∶00) from twoI. sinensis populations in China. One population occurs in the eulittoral zone of a freshwater tidal river at low elevation (134 m) and another occurs in a densely vegetated, high elevation (1 100 m) alpine shallow pool. Significant differences in pH and titratable acidity of the plant extract were detected between the morning and afternoon samples. These changes are associated with diurnal changes in water chemistry. Our results provide the first evidence for the existence of the CAM pathway in the East Asian endemicIsoetes sinensis Palmer. The magnitude of fluctuations in the titratable acidity of the plant extract may be correlated with the severe carbon limitation imposed on the plants by its aquatic habitat. Foundation item: Supported by the State Key Basic Research and Development Plan (G2000046805) Biography:Pang Xin-an (1974-), male, Master candidate, research direction: conservation biology.  相似文献   

8.
为观察骨碎补对去卵巢大鼠骨微结构的作用并探讨其可能作用机制,将36只大鼠分为实验组(OVXDF)、模型组(OVX)和假手术组(SHAM)。OVXDF及OVX组去卵巢造模,术后8周,测量3组大鼠骨密度后,OVXDF组给予骨碎补水煎液灌胃,OVX及SHAM组给予生理盐水灌胃,灌胃12周。然后利用Micro-CT测量骨密度BMD(g/cm3)、骨矿含量BMC(g)、骨小梁骨量BV/TV(%)、骨小梁厚度Tb.Th(μm)、骨小梁数量Tb.N(mm-1)、骨小梁分离度Tb.sp(mm)、结构模型指数SMI,显微镜下观察骨组织显微形态情况,酶联免疫吸附法测定大鼠血清TRAP、MMP-9、CTX-1含量。结果显示大鼠去卵巢后,不仅表现为骨量的降低,同时出现骨微细结构的变化,骨碎补灌胃后可以有效地对抗去卵巢大鼠的骨密度降低及骨微细结构的变化,其作用机制与其抑制骨髓脂肪细胞生成、抑制破骨细胞活性及数量有关。  相似文献   

9.
0 IntroductionMioclroogincuatlri pernotsce pslsaeys afo vrer wyais tmepwoarttaernt t rroelaetmine nbti- .A widerange of micronutrientsis required byactiva-ted sludge[1-5]. Adequate trace nutrient concentra-tions ,including metal ions and vitamins , are re-quiredtosupport all the genera presentinthe activa-ted sludgetreatment systemfor a diverse communityto survive. The lack of specific nutrients may resultin an unbalanced mixed culture,leading to poor-quality effluent , reduced treatment effic…  相似文献   

10.
Silicon ( 111 ) and Silicon (100) have been employed for fabrication of TiO2 films by metal organic chemical vapor deposition (MOCVD). Titanium (Ⅳ) isopropoxide (Ti[O (C3H7)4 ])was used as a precursor. The as-deposited TiO2 films have been characterized with Field emission scanning electron microscopy (FE-SEM), X ray diffraction (XRD) and atomic force microscopy (AFM). The photocatalytic properties were investigated by decomposition of aqueous orange Ⅱ. The crystalline and structural properties of TiO2 film had crucial influences on the photodegradation efficiency. For MOCVD in-situ deposited films on Si substrates, thephotoactivities varied following a shape of “M”: At lower (350 ℃ ) middle (500 ℃) and higher (800 ℃) temperature of deposition, relative lower photodegradation activities have been observed. At 400 ℃ and 700 ℃ of deposition, relative higher efficiencies of degradation have been obtained, because one predominant crystallite orientation could be obtained as deposition at those two temperatures, especially a single anatase crystalline TiO2 film could be obtained at 700 ℃ growth.  相似文献   

11.
探讨基于斑马鱼模型的不同浓度的氨基葡萄糖盐酸盐及淫羊藿提取物的促进骨骼矿化活性。选用发育正常的72 hpf斑马鱼胚胎,以培养水为溶剂对照,各受试组分别加入不同浓度(1、10和100 μg/mL)的氨基葡萄糖盐酸盐溶液或淫羊藿提取物溶液,连续培养4 d后,用体积分数为0.2 %钙黄绿素染色1 h,在体式荧光显微镜下观察斑马鱼骨骼发育情况,拍照并用图像分析软件计算骨骼染色面积。与对照组相比,各受试组对斑马鱼骨骼矿化均呈现一定程度的促进作用,且呈现明显的剂量依赖性。氨基葡萄糖盐酸及淫羊藿提取物均具有较好的促进斑马鱼骨骼矿化的活性。相同浓度条件下,氨基葡萄糖盐酸盐较淫羊藿提取物具有更好的促进骨骼矿化活性。  相似文献   

12.
0 IntroductionAsgue-br-eclaaptseudl acrat acraatcatr ianctc l,ud aems ocnogrte xwh,incuhcl,e acro ratnexdcataract and nuclear cataract are more i mportant .Cortex cataract is different from nuclear cataract inoccurring,developing and clinic display,evenin his-tology. The pathogenesis of age-related cataract hasnot been perfectly described.But it has been verifiedthat thereis alayer oflens epithelial cells (LECs) un-der vertebrates’lens anterior capsule, which is i m-portant in maintaining t…  相似文献   

13.
A series of experimental methods including 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) test, alkaline phosphatase (ALP) activity measurement, mineralized function, Oil Red O stain and measurement were employed to assess the effect of Dy3+ on the osteogenic and adipogenic differentiation of mouse primary bone marrow stromal cells (BMSCs) and the adipogenic trans-differentiation of mouse primary osteoblasts (OBs). The results showed that Dy3+ had no effect on BMSC proliferation at concentrations of 1×10−8 and 1×10−5 mol/L, but inhibited BMSC proliferation at other concentrations. Dy3+ had no effect on OB proliferation at concentrations of 1×10−10 and 1×10−9 mol/L, but inhibited OB proliferation at other concentrations. Dy3+ had no effect on the osteogenic differentiation of BMSCs at concentrations of 1×10−9 and 1×10−7 mol/L, and promoted osteogenic differentiation of BMSCs at other concentrations at the 7th day. The osteogenic differentiation of BMSCs was inhibited by Dy3+ at concentration of 1×10−5 mol/L at the 14th day, but promoted osteogenic differentiation of BMSCs at concentrations of 1×10−9, 1×10−8, 1×10−7 and 1×10−6 mol/L with the maximal effect at concentration of 10−6 mol/L. Dy3+ promoted mineralized function of BMSCs at any concentration. Dy3+ had no effect on adipogenic differentiation of BMSCs at concentration of 1×10−7 mol/L, but inhibited adipogenic differentiation of BMSCs at other concentrations. Dy3+ inhibited adipocytic trans-differentiation of OBs at any concentration, suggesting that Dy3+ had protective effect on bone and the protective effect on bone may be mediated by modulating differentiation of BMSCs away from the adipocyte and inhibiting adipocytic trans-differentiation of OBs which may promote differentiation and mineralization of OBs. These results may be valuable for better understanding the mechanism of the effect of Dy3+ on pathogenesis of osteoporosis. Supported by the Foundation for Key Program of Ministry of Education of China (Grant No. 208018)  相似文献   

14.
Sensitive Determination of DNA by RLS Enhancement of Metal Ions   总被引:1,自引:0,他引:1  
0 IntroductionThequantitativeanalysisofnucleicacids,especiallythemi cro determinationofnucleicacids,isbecomingmoreandmoreimportantinmanybiologicalstudies.Recently ,apromisingspectraltechnique ,whichwasbasedonthemeasurementofen hancedresonancelightscattering (RLS) [1 ,2 ] ,hasgivenrisetostronginterestbyanalystsandbiochemistsfornucleicacidsandproteinassay[3 9] .Uptonow ,manykindscompoundshavebeenfoundRLSenhancementwhilebindingtoDNA ,andallthesecompoundsarecharacterizedofpositivechargewhicha…  相似文献   

15.
Vibrio pacini synthesizes multiple chitinases, of which three have been purified in this study by ammonium sulphate fractionation, chitin affinity chromatography and gel chromatography. Molecular weights of the three chitinases, Chi1, Chi2 and Chi3 are 27×103, 39×103 and 46×103 respectively, as determined by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The purified enzymes have optimal activity at pH 7–8, and retain 50% enzymatic activity pH 4–9. The activities of chitinases are inhibited by Pb2+, Fe3+ and Cu2+, and increased by Ca2+, Mg2+ and Mn2+. Chi3 is found to inhibit the growth of six species of fungi. Such characters of chitinase are different from those of any other chitinase that were reported before. Foundation item: Supported by the Key Technologies Research and Development Programme of the Tenth Five-Year Plan of the Nation Scientific and Technological Development (2001 BA708B04-07) Biography: HAN Bao-qin (1963-), female, Professor.  相似文献   

16.
毛郁金乙醇提取物降血脂作用研究   总被引:2,自引:0,他引:2  
【目的】研究毛郁金(Curcuma aromatica)乙醇提取物降血脂作用,为其综合开发利用提供依据。【方法】通过高脂饲料喂养及脂肪乳剂灌胃,建立高脂血症大鼠模型,连续3周给予毛郁金乙醇提取物进行治疗,设正常组、高脂模型组、辛伐他汀组和毛郁金乙醇提取物高、中、低剂量(生药18g·kg-1·d-1,12g·kg-1·d-1,6g·kg-1·d-1)组,以动物实验研究毛郁金乙醇提取物降血脂的作用。【结果】毛郁金乙醇提取物可降低大鼠血清总胆固醇(CHOL)、三酰甘油(TG)和低密度脂蛋白(LDL-C)的含量,并提高血清高密度脂蛋白(HDL-C)含量,对血清CHOL、LDL-C的降低作用:高中低剂量组,中剂量组对降低TG、升高HDL-C含量具有较好作用,毛郁金各给药组均对大鼠血清LDL-C含量有极显著降低作用。【结论】毛郁金乙醇提取物具有明显的降血脂作用。  相似文献   

17.
To explore chronic eration and activation of mast heterotypic stressors induced prolifcells in gastric antrum mucosa by ultrastructure alterations of mast cells, chronic unpredictable heterotypic stressors were used as a study model. The mean immunofluorescence magnitude of mast cell protease 1 (MCP-1) taken from chronic stress rats were 37.4±7.7, significantly higher (p〈0.05) than the value of normal control group (24.8±5.6). Chronic unpredictable haterotypic stressors appeared also to induce ultrastructure alterations of mast cells. It indicated that mast cells were proliferated and activated, while mast cell granules were hyperplasiaed. Most granules had obvious intragranular changes with loss of electron-dense material. The morphologic evidence showed that macrophages and leukocytes infiltrated in chronic stress rats. Some granules of leukocytes adhered to the surface of mast cell, and formed a bridge. Macrophages phagocytized the mast cell granules.  相似文献   

18.
This paper presents a novel probability generation algorithm to predict attacks from an insider who exploits known system vulnerabilities through executing authorized operations. It is different from most intrusion detection systems (IDSs) because these IDSs are inefficient to resolve threat from authorized insiders. To deter cracker activities, this paper introduces an improved structure of augmented attack tree and a notion of "minimal attack tree", and proposes a new generation algorithm of minimal attack tree. We can provide a quantitative approach to help system administrators make sound decision.  相似文献   

19.
20.
0 IntroductionMolecularimprinting[1 ] isatechniquebasedoncreatingcavities,inahighlycross linkedpolymermatrix ,thatcorrespondtothesizeandshapeoftheprintmolecule .Themolecularrecognitioneffectisaconsequenceofthepresenceinthepolymerizationmixtureoftemplatemoleculescapableofestab lishingnon covalentinteractionswithmonomerandcross linkers.Molecularlyimprintedpolymers (MIPs)havebeenusedaschromatographicstationaryphases[2 ,3] includingcapillaryelec trochromatography ,asselectivematerialsforbiosenso…  相似文献   

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